I'm new to the forum. I would like to thank you all in advance for coming to my post and sharing your expertise. I'm about to move abroad and would like to know what to buy in order to have a decent home theater and wireless music streaming system. The home theater will be for playing movies/series, but also to occasionally watch soccer on public TV, with an HD antenna.

As you could see in this diagram (http://imgur.com/gRKcIwQ), I'd like to stream music from my iphone and laptop into the speakers. If I don't get speakers with AirPlay, I will get an Airport Express and plug them in. So far, so good.
I would also like to use the same speakers in conjunction with a projector (w/ an HDMI port) to play videos/TV.
(1) If the speakers have AirPlay (either natively or through the Airport Express), could I alternate the input between the music and video? Is this hard to do?

My main predicament is how to input TV signal and movies into the projector/speakers. An Apple TV wouldn't work because it doesn't let me play movies that I have in a HDD, correct?. Ideally, I would like to have an external HD disk connected to a router, and play the movies from there. But assuming this is not possible (please correct me if I'm wrong), I need an alternative. Another media center?
Does anyone see a solution? I'm trying to avoid having a computer connected to the apparatus, at all costs.

Thank you SO much for your willingness to help, and have a great weekend,

A receiver has about 6 HDMI inputs and 1 HDMI outputs.
I'm hoping I could get:
-- the Air TV decoder/tuner into the receiver via HDMI, then to the projector & speakers
-- the music into the speakers funneled through the receiver (via AirPlay, which the receiver has)
-- movies from the WD Live into the projector & speakers.

Is this feasible or am I missing something? Can the receiver relay the video signal?